1. Field of the Invention
This invention relates the field of retractable and adjustable tarpaulins, particularly those that cover the bedplate of a trailer.
2. Description of the Prior Art
Certain patents particularly drew our attention:
U.S. Pat. No. 5,690,377, Denyer, Nov. 25th , 1997, the box cannot be lowered and the tarpaulin covers only the top part of the load.
U.S. Pat. No. 5,524,953, Shaer, Jun. 11 th, 1996, is a tarpaulin installed on arches, which slide along two rails. It cannot be adjusted for different heights.
U.S. Pat. No. 5,988,732, Schouten, Nov. 23rd , 1999, shows means of manuvering a tarpaulin but without varying the height or the length to be covered. The system uses several gears. It is heavy to handle and expensive to build.
U.S. Pat. No. 4,023,857, Killion, May 17th, 1977 shows a retractable tarpaulin. The frame of the box does not vary.
FR 64,559, Justinien, shows a permanent lattice, covered by a tarpaulin, which can be unfolded from the front to the rear. A tarpaulin, also present on both sides, folds around a roller 23. Neither the height, nor the length can be adjusted.
It is a general objective of the invention to provide a tarpaulin which can cover the cargo of trailers and is adaptable to various lengths, widths and heights. This tarpaulin should cover various cargos easily and securely. It should also be foldable into a small roll for storage. Its simple structure and light weight is to make it possible to cover a cargo entirely or in part. A more particular objective is to provide posts that are installed into notches in rails located at the periphery of the flat bed of a trailer. These posts are to be moved in accordance with the length of the cargo to cover. The length of these posts is to be adjustable to adapt to the height of the cargo. The end posts are linked together by cables to create a net that will support the tarpaulin.